Incandescent electric lamp.



J. J. RODNEY.

INCANDESCENT ELECTRIC LAMP.

APPLICATION PILEDJAN.5,1910.

Patented Jan. 5, 1915.

In ycntor:

A ttys;

v Joiaii J. accuse, or NEW YORK, N. Y.

iisrcanmiscsn r ELECTRIC. LAMP.

Teal! go'hom it"ma'y'concem} 1% it zth r o i Q E citizen of the United 'states, residingkat No.

St. Johns- P1ace,-'in the borough of Brooklyn of l the" city of Ncw York, in the State of-"New York,-have invented certain new and useful Impro'vements in Incandes cent Electric Lamps,.='of which. thbiollowing is .a specification, reference being had to the accompany ng drawing, forming a part hereof.

' This invention relatesto so-called'q turndown incandescentfl electri'c lamps, and more especially. to turn-down lamps of the type of that shown in Letter-s Patentof the United States No. 480,951, dated August 16,

189% in whichtwofilaments are. connected in series, the rela'tion'of such filaments being such that one of the? filaments is caused to glow while the' othjer remains, dark when the current passes .t-hroughthem in' series, while provision is ,i'nad'e' whereb .the current may be sent through'one of the filamentsalon'e while the other 'is-"cutxout the filament which". is thus. caused to-glow being other than the'ifilanient'which'is' caused 'to' glow when. the current passes through the two filaments in series. i

.I he inventioni's particularly. Concerned with the devices for cutting one of. the fila- -ments out of the circuit, one object of the invention being to-permit the use of copper contacts so as to reduce the liability of arcing, and another object being to permit cut out or turn-down devices of the same general character as those'shown in said patent to be operated by cords rathcr than by the direct application of the fingers.

The invention i-will be more fully ex- 'plained hereinafter with reference to the accompanying drawing, in which Figure 1 1s a view in elevation of a lamp with the invention applied thereto. Fig. 2

. is a detail viewlin section, on a larger scale.

Fig. 3 is a detail front elevation of the switchshowing the parts in the position they assume when'bein'g assembled. FiH. 4 is a vertical section on the line 4-1 of Fig. 3. Fig. 5 is a detail view in section on the plane indicated by the line 5-5 o'f Fig. 2,

but on a largerscale' Fig. 6 is a detail view 1n vertical 'crosssecti'on on the plane ind "cated by the line 6-6 of Fig. 5.

I The lamp shown in the drawing is of ordinary-constiuetion, except so far as the turmdowndetrices are concerned, compris- Specification of Letters Patent.-

Patented an. 5-, 1915.

a uauo filed January 5, 1910. a Serial m. 536,545.

inga bulb a, a screw threaded shellb for insertion in a similarly threaded socket and in which the neck of the bulb is'sea'ted and secured by suitable. cement c or other suit-1 able means, a large filamentd and a's'mall filaments. One end of the large filament d 'providedto controrthesupply of current; to.

the lamp In theirnproved lamp, the shell 11 forms one of the lamp terminals, the leading in wire of the filament ye, being connected directly thereto, and provision is made whereby the common .connectione=,of the two fila-' ments is electrically connected with the shell- 6 when the-filament e is-to be cut out or short circuited. "To .this end a screw threaded post 1 is secured directly to the. shellb, inelectrical contact therewith near.- the edge thereof. A strip 9 of fiber or other, suitable insulating material is folded over" the edge of the shell I), having in its outer portion an aperture to receive the stud f. A strip h, of copper. preferably'having the form shown in Fig. 3, andvhaving a hole h of such size as to receive the stud f.- "-"-ith' sufiicientclearance to avoid the possibility of contact with the stud, is placed upon the stud and its end portion Ii is folded over the edge of the shell b. An insulating washeri, of fiber or other suitable material, is then slipped 'upon the stud f, andthe other portion of the copper strip h. is folded over it and over the edge of the shell I), the narrow portion h of the copper strip overlying the washer 1'- at one side of and in juxtaposition to the stud f and out of contact therewith. 'It will be understood. of course, that the insulating strip g lies between the shell I) and the copper strip h, so that the latter is completely insulated from the stud f and from the shell I), the insulating strip being wider than the copper strip. On the stud f is mounted a circuit closer in the form of a nut or screw threaded disk In which, when screwed home against the portion h of the copper contact strip, completes the circuit between the stud and the copper con tact strip and, since" the common connection e of the filaments is electricall connected to one end ofcthe contact strip; as shown in FigQ 2, the circuit is therefore completed from the leading in-wire (1' through the filament d and the common connection eito the shell 1;, thereby short circuiting the filamente. V v p f The threadedfiisk or nut. his preferably a of copper soth'atthe arcing between the two contacts h'andik, was the circuit is closed or opened, is reduced to aminimum. .For con-'- venience in operation of t'he disk 70- a cord l is connected to thedisk, at its edge,- and the two parts 1 and 1 thereof are led through suitable guides m" and m, mounted on the shell b,-so' that a pull upon one card rotates motion-through a smallfarc shallwith oertainty close. the circuit, while a corresponding rotation gofqthe diskinv theopposite'direction shallopen the circuit. v

It will be seen thatthe'stud f is jfirmly secured to theshell and is not'li le tebe pulled out as would be the case it werej' necessary to' insulate the stud from the shell,v

while at the same time, the parts "arefso arranged that danger of accidental sliin't circuiting is eliminated and the desired opera-.

tion can be effected with certainty.

to. said disk to rotate I claim as my invention.

1. A switch for incandescent electric lamps comprising a stud secured to the shell of the lamp and in electrical contact therewith, an insulating strip perforated to receive the .stud and folded overthe edge of the shell,

an insulating washer on the stud, a contact str p having a, perforation to receive the stud and slipped upon the stud between the shell and the washer and folded over the washer and over the edge ofthe shell and having the common connection of the filamen'ts of the lamp electrically connected therewith, a circuit closer mounted movablv' on the stud and movable to complete the circuit between the sameand the portion of the contact strip overlying the washer and cords connected to said circuit closer-. to

move the same.

2. A switch for incandescent electric lamps com'prisin a screw threaded stud secured to the shel of the" lamp and in electrical contacttherewith, a contact to which the commonconnection of theffilaments is electrically connected, said cont-act being.

mounted in juxtapositionto' the stud but insulated therefrom .and from the shell, a screw. threaded disk-like c1 rcuit closer .mounted on the stud and adapted to cemplcte the circuit between the same andsaid contact when screwed i me, cords connected in one directiongorthe'cther and guides for-the cords, said disk-like I uit' closer'having a series of holes about rtscircumference in any one of which the cords may be connected.

This specification signed and witnessed this 16th day of November A. D.'1909.

l JOHN J. RODNEY. Signed in the presence 'of'- ELLA J. Knuosinf Amnnossjjt OSHEA. 

